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101.
We discuss the role of tangential stabilization in a curvature driven flow of planar curves. The governing system of nonlinear parabolic equations includes a nontrivial tangential velocity functional yielding a uniform redistribution of grid points along the evolving family of curves preventing numerically computed curves from forming various instabilities. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
102.
Dr. Manuel Souto Dr. Karol Strutyński Dr. Manuel Melle-Franco Prof. João Rocha 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(48):10912-10935
Electroactive organic molecules have received a lot of attention in the field of electronics because of their fascinating electronic properties, easy functionalization and potential low cost towards their implementation in electronic devices. In recent years, electroactive organic molecules have also emerged as promising building blocks for the design and construction of crystalline porous frameworks such as metal–organic frameworks (MOFs) and covalent-organic frameworks (COFs) for applications in electronics. Such porous materials present certain additional advantages such as, for example, an immense structural and functional versatility, combination of porosity with multiple electronic properties and the possibility of tuning their physical properties by post-synthetic modifications. In this Review, we summarize the main electroactive organic building blocks used in the past few years for the design and construction of functional porous materials (MOFs and COFs) for electronics with special emphasis on their electronic structure and function relationships. The different building blocks have been classified based on the electronic nature and main function of the resulting porous frameworks. The design and synthesis of novel electroactive organic molecules is encouraged towards the construction of functional porous frameworks exhibiting new functions and applications in electronics. 相似文献
103.
Bulko Martin Holý Karol Brandýsová Alžbeta Müllerová Monika Masarik Jozef 《Journal of Radioanalytical and Nuclear Chemistry》2021,328(2):651-657
Journal of Radioanalytical and Nuclear Chemistry - In this study, five different methods for determining the geogenic radon potential are compared in the Mochovce region, Slovakia. Based on these... 相似文献
104.
105.
We study a model of complex band random matrices capable of describing the transitions between three different ensembles of Hermitian matrices: Gaussian orthogonal, Gaussian unitary and Poissonian. Analyzing numerical data we observe new scaling relations based on the generalized localization length of eigenvectors. We show that during transitions between canonical ensembles of random matrices the changes of statistical properties of eigenvalues and eigenvectors are correlated. 相似文献
106.
A hierarchy of functions with respect to their role as bounds in the Turing reducibility of functions is introduced and studied. This hierarchy leads to a certain notion of incompressibility of sets which is also investigated. 相似文献
107.
108.
Teresa Kowalik-Jankowska Henryk Kozlowski Karol Kociolek Miroslaw T. Leplawy Giovanni Micera 《Transition Metal Chemistry》1995,20(1):23-25
Summary Potentiometric and spectroscopic measurements were used to characterize the binding ability of -hydroxy-methylserine (Hms) with copper(II) and oxovanadium(IV) ions. The ligand was found to be generally a more efficient chelating agent than serine. Both of the deprotonated hydroxyl groups of Hms can be involved in coordination to vanadyl ions, whereas copper(II) binds in the same way as with serine. 相似文献
109.
A convergence characterization of the Galerkin-Petrov method by means of quantities characterizing pairs of subspaces is presented. The usefulness of our approach for setting up reliable computational schemes is demonstrated for the He atom ground state. Several methods of constructing pairs of subspaces for use in quantum chemistry are suggested. 相似文献
110.
The Raman spectra of N2O4 solutions in organic solvents have been recorded. The frequencies ofv
1,v
2, andv
3 bands of N2O4 increase with increasing solvent electron-donor properties. Especially large changes ofv
3 N-N stretching band have been observed (254.5 cm–1 in n-hexane, 276.5 cm–1 in 1,4-dioxane). The ab initio calculations have shown that the interaction between N2O4 and electron-donor molecules causes an increase of N-N and N-O stretching and O-N-O bending force constants of N2O4 in agreement with the results of Raman study. 相似文献